1. Field of the Invention
The present invention relates to a striking tool such as a hammer, a hammer drill which is configured to position a cylinder at inside of a cylinder case.
2. Description of the Related Art
A striking tool of a related art will be explained in reference to FIG. 6 through FIG. 8.
As shown by the drawings, a striking tool of a related art is configured by a structure including a motor 1, a cylinder 2, a cylinder case 3 covering an outer periphery of the cylinder 2, a tool holding portion 5 capable of holding a front end tool 4, a piston 6 capable of reciprocating at inside of the cylinder 2, a striker 8 reciprocating at inside of the cylinder 2 by being exerted with a reciprocating force of the piston 6 via an air chamber 7, a breathing hole 9 provided at the outer periphery of the cylinder 2 and communicatable with the air chamber 7, a crankshaft 11 exerted with a rotational force of the motor 1 via a reduction gear 10 and converting the rotational force into the reciprocating force to transmit to the piston 6 via a connecting rod 12, a middle piece 13 struck by the striker 8 and capable of transmitting a strike force thereof to the front end tool 4, a slide sleeve 15 provided on the outer periphery of the cylinder 2, urged to a side of the middle piece by a spring 14, and capable of opening and closing an outer periphery of the breathing hole 9 in accordance with a moving position thereof, a cylinder holder 16 brought into contact to be fitted with an end face of the cylinder 2 on a side of the tool holding portion and having three foot portions 16a (FIG. 7), a first hammer holder 17 an end portion of which is brought into contact with an end portion of the slider sleeve 15 and which includes three foot portions 17a arranged among the respective foot portion 16a of the cylinder holder 16, a second hammer holder 18 an outer periphery of which is held by the first hammer holder 17 and capable of being brought into contact with a portion of the middle piece 13 opposed thereto, and a buffer member 19 arranged between the first hammer holder 17 and the second hammer holder 18 in which the cylinder 2 is provided with a flange portion 2a projected in a radius direction on a side of the motor 1, and the cylinder case 3 is provided with a butting face 3a capable of being brought into contact with the flange portion 2a and a first holding portion 3b brought into contact with the outer periphery of the cylinder 2 on a side of the motor 1 to position in a radius direction.
As shown by FIG. 8, an inner diameter dimension of the first holding portion 3b is formed to be a dimension substantially the same as an outer diameter dimension of the cylinder 2 and in this way, a vicinity of the end portion of the cylinder 2 on the side of the motor 1 is positioned in the radius direction by the first holding portion 3b. 
Further, positioning of the cylinder 2 in the radius direction on a side of the tool holding portion 5 is carried out by bringing a second holding portion 3c having an inner diameter of a dimension substantially the same as an outer diameter dimension of the cylinder holder 16 into contact with the cylinder holder 16. (refer to, for example, JP-A-2003-300180).